1 | /* s_ceill.c -- long double version of s_ceil.c. |
2 | * Conversion to IEEE quad long double by Jakub Jelinek, jj@ultra.linux.cz. |
3 | */ |
4 | |
5 | /* |
6 | * ==================================================== |
7 | * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. |
8 | * |
9 | * Developed at SunPro, a Sun Microsystems, Inc. business. |
10 | * Permission to use, copy, modify, and distribute this |
11 | * software is freely granted, provided that this notice |
12 | * is preserved. |
13 | * ==================================================== |
14 | */ |
15 | |
16 | #if defined(LIBM_SCCS) && !defined(lint) |
17 | static char rcsid[] = "$NetBSD: $" ; |
18 | #endif |
19 | |
20 | /* |
21 | * ceill(x) |
22 | * Return x rounded toward -inf to integral value |
23 | * Method: |
24 | * Bit twiddling. |
25 | */ |
26 | |
27 | #include <math.h> |
28 | #include <math_private.h> |
29 | |
30 | _Float128 __ceill(_Float128 x) |
31 | { |
32 | int64_t i0,i1,j0; |
33 | u_int64_t i,j; |
34 | GET_LDOUBLE_WORDS64(i0,i1,x); |
35 | j0 = ((i0>>48)&0x7fff)-0x3fff; |
36 | if(j0<48) { |
37 | if(j0<0) { |
38 | /* return 0*sign(x) if |x|<1 */ |
39 | if(i0<0) {i0=0x8000000000000000ULL;i1=0;} |
40 | else if((i0|i1)!=0) { i0=0x3fff000000000000ULL;i1=0;} |
41 | } else { |
42 | i = (0x0000ffffffffffffULL)>>j0; |
43 | if(((i0&i)|i1)==0) return x; /* x is integral */ |
44 | if(i0>0) i0 += (0x0001000000000000LL)>>j0; |
45 | i0 &= (~i); i1=0; |
46 | } |
47 | } else if (j0>111) { |
48 | if(j0==0x4000) return x+x; /* inf or NaN */ |
49 | else return x; /* x is integral */ |
50 | } else { |
51 | i = -1ULL>>(j0-48); |
52 | if((i1&i)==0) return x; /* x is integral */ |
53 | if(i0>0) { |
54 | if(j0==48) i0+=1; |
55 | else { |
56 | j = i1+(1LL<<(112-j0)); |
57 | if(j<i1) i0 +=1 ; /* got a carry */ |
58 | i1=j; |
59 | } |
60 | } |
61 | i1 &= (~i); |
62 | } |
63 | SET_LDOUBLE_WORDS64(x,i0,i1); |
64 | return x; |
65 | } |
66 | weak_alias (__ceill, ceill) |
67 | |